Preservation of Ovarian Function After Hematopoietic Cell Transplant

This study is to use gonadotropin releasing hormone (GnRH) agonist leuprolide prior myeloablative hematopoietic cell transplantation to prevent ovarian dysfunction in post-menarchal women. The primary objective is to determine the effect of GnRH agonists on the incidence of ovarian failure. The secondary objectives are * to determine how effective GnRH agonists are at suppressing menses during * to determine the incidence and timing of resumption of menstrual cycles after HCT * to determine the incidence and timing of resumption of normal FSH and LH levels after HCT * to determine the incidence of normal AMH levels after HCT * to determine the effect of GnRH agonists on immune reconstitution after HCT * to assess the safety and tolerability of GnRH agonists in the context of HCT A total of 47 patients will be accrued in this study.